Apparatus for use in the manufacture of slide fasteners



H. HANSEN June 28, 1960 APPARATUS FOR USE IN THE MANUFACTURE OF SLIDE FASTENERS Filed Nov. 20, 1957 3 Sheets-Sheet 1 INVENIOR QQ, aflwza.

ATTORNEY June 28, 1960 H. HANSEN 2,942,336

APPARATUS FOR USE IN THE MANUFACTURE OF SLIDE FASTENERS Filed NOV. 20, 1957 3 Sheets-Sheet 2 ATTORNEY H. HANSEN June 28, 1960 APPARATUS FOR USE IN THE MANUFACTURE OF SLIDE FASTENERS Filed Nov. 20, 1957 3 Sheets-Sheet 3 UIEIEIUUDUDDkj' UEIUEJDEIDUEIi INVENTOR ATTORNEY BY J/J United States APPARATUS FOR USE IN THE MANUFACTURE OF SLIDE FASTENERS Harry Hansen, 14 Hgziftdingsvej, Valby (Copenhagen),

' Denmark Filed Nov. 20, 1957, Ser. No. 697,713

Claims priority, application Denmark Dec. 3, 1956 q 9 Claims. (Cl. 29-208) In slide fasteners it is very important that the'coupling links of the two rows to be engaged with one another should be positioned at exactly the same and, within each row of coupling links, exactly uniform spacing, since otherwise difficulties will arise as regards proper engagement.

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In the case of slide fasteners, in which the two rows of coupling links are of different construction, the said method cannot beused. One example of this is a slide fastener, in which one row of coupling links consists of a coiled filament, while the other row of coupling links consists of a filament bent in serpentine form, as described in my copending application Ser. No. 592,915 now Patent No. 2,907,088, issued October 6, 1959. In such cases, it becomes necessary to attach the rows of coupling links to'the two tapes in different machines and the required accuracy, within which a prescribed spacing of the coupling links should be maintained, will therefore be much more critical.

Also in slide fasteners, in which the rows of coupling links are identical, it may be advantageous from a manufacturing point of view to organize the manufacturing process in such a manner that it is not necessary to take the two stringers, i.e. tapes with rows of coupling links thereon, from the same coupling link attaching machine.

Finally it should be mentioned that in slide fasteners with rows of coupling links formed from a continuous filament and attached to the tapes by sewing, the required accuracy of the coupling link spacing is as a generalrule much more critical than in slide fasteners with individually attached coupling links.

Thus, it is desirable, from many different points of view, to develop machines for attaching rows of coupling 'links to tapes at an extremely accurate spacing.

The invention is based on the recognition that the greatest difiiculty in solving this problem results from the elasticity of the tapes. The fact is that during the process of attaching the coupling links and especially during the feeding of the tapes to the position of attaching the tapes are invariably subjected to forces that tend chine, according to which, while coupling links are being attached to a tape in a progressing operation, the said tape is kept pressed between .two conveying members at the point where the attachment is taking place and over a distance before and after the said point. In this manner, the tape is subjected to a positive holding pressure over a relatively long distance and especially over a con siderable distance before the zone where the attachment of the coupling links is taking place, and this again means that the tape is positively guided through the machine in such a manner that it has no possibility of expanding or contracting under the influence of the forces, to which it is subjected during the link attaching operation.

It is very important, according to the invention, that the tape should be passed-to and in between the conveying members in a practically relaxed or untensioned state, so that it will not, before being pressed between the conveying members, be subjected to forcesthat might stretch it in uncontrollable manner.

With particular advantage, according to the invention, conveying members may be used in the form of synchronously moving bands having parallelly extending runs, which are urged towards one another in a guide path. Preferably, the tape may then be passed in between the conveying bands in such a manner that the tape with the exception of the marginal zone, in which the attachment of the coupling links is to take place, is held by pressure between the conveying bands, while the said marginal zone extends laterally beyond the edges of the conveying bands.

On principle the machine may be used for slide fasteners of any type, but as mentioned it is particularly important for slide fasteners with rows of coupling links formed from a continuous filament, and in that case, according to the invention, a continuous row of coupling links may be guided into a path extending alongside the conveying members for the purpose of being attached by sewing to a marginal zone of the tape extending laterally beyond the edges of the conveying members.

It is a special problem to guide a row of coupling links of this type in such a manner relative to the tapes that all of the convolutions of the coil will assume the same angular position, viz; as a rulesuch that the convolution portions having the smallest angle of pitch, if desired zero angle of pitch or even slightly negative angle of pitch, will face away from the tape. To serve this problem, according to the invention, the row of coupling links is caused to move, in part of its feeding path, along the side of and in engagement with a threaded spindle having the same total rise. per convolution as the row of coupling links, but a substantially greater diameter'than the latter. It has been found that such a screw spindle will tend to turn the coiled row of coupling links about its axis into a position such that the convolution portions of the coiled row of coupling links having the smallest angle of pitch-or in other words the angle of pitch coming closest to that of the spindle-will accommodate themselves between the screw thread tops of the spindle so that thecoiied row of coupling links, in a zone shortly ahead of the position where it is to be sewn to a tape, will assume a definite angular position in its feeding path.

When such a screw spindle is used, this may advantageously at the same time be utilized for producing gaps in the attached row of coupling links at the positions where the tape is to be subsequently severed to form individual slide fasteners. To this end, according to the invention, the row of coupling links is cut through at suitable intervals of tape length in a point following the threaded spindle and the latter is momentarily stopped.

The invention also relates to an. apparatus for carrying out the described method. The characteristic feature-of this apparatus, enabling the method to be carried out in a practical and advantageous manner, is to be seen in the fact that the apparatus comprises two synchronously moving conveying members, which over a distance thereof are adapted to grip a tape for a slide fastener between themselves in a position such that a marginal zone of said tape extends laterally beyond the edges of the conveying members, means for urging said conveying members against one another over the said distance so as to cause said tape to be held non-displaceably therebetween, and means constructed to permit the operation of coupling link attaching means within a limited part of said distance.

The invention will now be described in further detail with reference to the accompanying drawing, in which Fig. 1 shows the more important parts of one form of an apparatus according to the invention, in plan view and partly in section, a

Fig. 2 an end view of same,

Fig. 3 a side view of same,

Fig. 4 on a strongly enlarged scale, a section along the line IV-IV in Fig. l, and b Fg. 5 a plan view of a section of one of the conveying an s.

In the drawings, 1 is a lower guide bar and 2 an upper guide bar, which combine to form a guide path for a tape 3 to which a row of coupling links '4 in the form of a coil is to be attached by sewing. Two endless metal bands 5 and 6 run in the guide path between the twoguide bars 1 and 2 and, outside the guide path, are passed over rollers 7, 8, 9 and 10, 11, 12 respectively, of which e.g. the rollers 9 and 12 may be synchronously running driving rollers with teeth engaging with holes in the marginal zones of the bands. In Figure 3, parts of the band are broken away and it is to be understood that the parts of the bands not shown form loops and are guided by means of rollers in suitable positions.

In the guide path between the guide bars 1 and 2 the bands 5 and 6 are pressed against one another e.g. by means of resiliently supported arms 13 and '14 acting on the upper guide bar 2. Thereby the bands 5 and 6 are caused to grip the tape 3 firmly between themselves, so

that the tape is positively moved by the conveyor bands 5 and 6 and is kept so firmly pressed between the latter that it cannot be displaced relative to these bands. The conveyor bands 5 and 6 may advantageously be constructed with perforations e.g. in the form of square windows as illustrated in Figure 5, whereby the frictional engagement between the conveyor bands and the tape is further improved. The tape 3 is held in a position such that only the marginal zone, to which the row of coupling links 4 is to be attached extends laterally beyond the edges of the conveyor bands 5 and 6 and the guide bar 2.

In the embodiment shown, the apparatus is constructed for attaching a row of coupling links in the form of a coiled filament by sewing to one marginal wing of a bifurcated tape e.g. such as described in my eo-pending application Ser. No. 607,810, now Patent No. 2,910,755, issued November 3, 1959. The tape should therefore be guided in such a manner that only one wing 15 will extend laterally from the conveyor bands 5 and 6, while the other wing 16 is bent backwards. To this end the tape, on its way to the interspace between the conveyor bands 5 and 6, passes through an entrance guide consisting of a lower guide block 17, an upper guide block 18 and a lateral guide block 19, the latter being constructed with a plough surface 20 forcing the wing 16 up into vertical position preparatory to its entrance between the block 19 and the block 18, while at the same time the wing 15 is accommodated in a groove 21 of the block :19 and the body portion of the tape 3 is guided between the lower guide block 17 and the upper guide block 18. The latter is attached to a bar 22, which by means of pins 23 and 24, that are slidably mounted in a fixed block 25, can be withdrawn against the action of a spring 26 when the tape is to be introduced. The frictional resistance in the entrance guide should be so small that it practically does not give rise to any tension in the tape.

When the tape is carried further forward between the conveyor bands 5 and 6, the vertically projecting wing 16 strikes another plough member 27, which bends the wing 16 downwards against the inclined upper surface of the guide bar 2. In this position the tape passes below a stitch plate 28 so that the wing 16 is accommodated between the upper side of the guide bar and the underside of the stitch plate 28, as illustrated in Figure 4. The tape is now ready for the attachment of the row of coupling links. The latter is fed forward through ;a passage 29 in the stitch plate 28, so that the coiled filament 4 forming the coupling links is thereby landed in correct position on top of the wing 15, to which it is to be attached by sewing. The sewing is effected by means of a sewing needle 30, which is moved up and down through a hole 31 of the stitch plate, preferably at an inclination as described in my said Patent No. 2,910,755.

The necessary means for supplying and guiding an underthread of the sewing seam may be accommodated in -a recess of the guide bar 1, but are not shown in the drawing, since they do not form part of the invention and in fact may be identical with those of a conventional sewing machine. If a trifurcated tape is used, the third wing 16' may be kept in a downwardly bent position in a groove of the guide bar 1 during the sewing as indicated in dotted lines. This may be effected by means of similar guide members as those used for bending the wing 16 backwards.

, Synchronism is established by conventional means, not shown, between the movement of the needle 30 and the feeding movement of the bands 5 and 6, so that the needle 30 in each of its movements passes through the space between two convolutions of the coil.

In the embodiment shown, the feeding of the helical row of coupling links 4 to the passage 29 takes place through a feeding passage 32 in a block 33, in which a screw threaded spindle 34 is rotatably mounted in such a position as to have one side extending alongside and projecting slightly into the feeding passage 32, so that the helical row of coupling links travelling through the feeding passage is forced to engage with the screw thread of the spindle 34. The screw spindle 34 is synchronized with the conveyor bands 5 and 6 and with the needle 30 in such a manner as to cause or permit feeding of the helical row of coupling links at the desired rate. If the helical row of coupling links has a smaller angle of pitch-if desired zero angle of pitch or even slightly negative angle of pitchover part of its circumference than over the remaining part of its circumference, the

portion of the convolutions having the smallest angle of pitch will automatically be attracted towards the side of the passage, along which the screw spindle 34 extends, because these portions of the convolutions come closest to the angle of pitch of the screw spindle, whereby the helical row of coupling links is angularly adjusted about its own axis in such a manner as to be fed forward along the tape in correct position, viz. such that the portion ofthe convolutions of the helical row of coupling links having the smallest angle of pitch will face away from the body portion of the tape.

In the embodiment shown, a knife '35 is arranged at the point of transition between the block 33 and the stitch plate 28, which knife is arranged in such a manner that it can be caused to cut through the helical row of coupling links at intervals such as is desirable when the row of coupling links is to be attached in the form of limited sections with a view to the subsequent sub division of the stringer into individual slide fasteners.

.The arrangement is such that the screw spindle 34 is stopped when the knife 35 cuts through the row of coupling links and is started again only after a certain relatively short period of time.

The attadlmfillfi Of a row of coupling links in the form of a serpentine can be efiected in similar manner as described and shown, only the special angular adjustment by means of the screw spindle 34 will not be necessary in this case. Besides, the basic arrangement comprising two conveyor bands or similar conveyor members may be used for the attachment of coupling links of any type and with the use of attaching means of face to face relationship through an elongated guide path, means for introducing a tape into the interspace' of the opposed faces of said conveying members in a position such that a marginal zone of said tape extends laterally beyond the edges ofthe conveying members, means for urging said conveying members against one another over thewhole length of the said guide path by a positive holding pressure over a relatively long distance including the distance before the zone where the attachment takes place so as to cause said tape to be held non-displaceably therebetween so that there is no expanding said contracting of the tape, and means constructed to permit the operation of coupling link attaching means in a point intermediate the ends of said guide path.

2. An apparatus as in claim 1, in which the conveying members consist of conveying bands, which over the distance, where they are to hold the tape between themselves, have a common path between guiding members.

3. An apparatus as in claim 1, in which means are.

provided for resiliently urging the guiding members to wards one another.

4. An apparatus as in claim 1, in which the conveying bands consist of thin metal bands with perforations.

5. An apparatus as in claim 1, in which a guide block is provided in association with the guide members, said guide block having a passage for feeding a continuous row of coupling links into a path alongside the conveying bands. in a position for attachment by sewing to the marginal zone of the tape extending laterally beyond the edges of the conveying bands. 7

6. An apparatus as in claim 5, in which the said guide block is provided with a sewing hole for the passage of a sewing needle serving to sew the row of coupling links onto the tape.

7. An apparatus as in claim 5, in which at the entrance end of the guide block there is provided a feeding passage, which over a distance extends axially along the surface of a threaded spindle.

8. An apparatus as in claim 7, in which means are provided for periodically cutting through the row of coupling links in a point following the screw spindle, and

for momentarily stopping the latter.

9. An apparatus for attaching a row of coupling links to a tape for making a stringer for a slide fastener, com

prising upper and lower guide members defining an elongated guidepath therebetween, a pair of continuously and synchronously moving conveying bands having concurrent runs extending and moving lengthwise through said guide path, means for introducing a tape into the interspace of said concurrent runs of said conveying bands in a position such as to have a marginal portion extending beyond the edges of said conveying bands at one side, means for urging said upper and lower guide members towards one another to press said tape therebetween at the point where the attachment is made and over a distance before and after said point whereby the tape is subjected to a positive holding pressure over a relatively long distance including a distance before said attaching point so that expanding and contracting of said tape under a the influence of forces to which it is subjected during the attaching operation, are prevented, means for feeding a row of coupling links in a path along the said edges. of said conveying bands synchronously with the movement of the latter, and means intermediate the ends of said guide path for attaching said row of coupling links to said tape.

References Cited in the file of this patent UNITED STATES PATENTS Schwartz Feb. 11, 1958 

